Information collected to establish where students are in their learning can be used for summative purposes (assessment of learning) and for formative purposes (assessment for learning) because it is used to inform subsequent teaching. The principles of assessment apply to all forms of assessments.
Summative assessment involves assessment procedures that aim to determine students' learning at a particular time, for example when reporting against the achievement standards, after completion of a unit of work or at the end of a term or semester. The aim of the assessment is to identify students' achievement at that point in time and it is particularly important that the assessments are fair and that teacher judgements are reliable.
Formative assessment involves a range of informal and formal assessment procedures used by teachers during the learning process in order to improve student attainment and to guide teaching and learning activities. It often involves qualitative feedback (rather than scores) for both students and teachers that focuses on the details of specific knowledge and skills that are being learnt. Therefore it is essential that the assessments provide fine-grained information about student performance that supports teachers to plan learning that challenges students to go beyond what they already know, understand or can do in order to build new knowledge, understandings and skills.
There is a growing body of research that shows that assessment is essential for effective teaching. Yet, you may feel that if you were to attend to the Principles of Assessment, you would have no time left to teach. One way of getting the correct balance is to consider the purpose of the assessment.
The other way to help you get the right balance is to examine to what extent an assessment informs your teaching. Only use assessments that give you worthwhile information and support you in improving student learning.